Square welted outdoor chair seat cushion 18 inch wide, 18 inch deep and 2 inches thick. Fits most square chair seats. Plush, soft but strong chair seat cushion. Cushion has piping all across the sides on both sides for strength. Contains zippers for removing covers. Covers are machine washable. Pair of ties in the back area for securing on chairs. Made with commercial hotel standards. Made from weatherproof and colorfast Sunbrella® fabric. Fits most outdoor patio chairs. Dimensions: 18W x 18D x 2H.